The effect of dietary crude protein level on ileal and fecal amino acid digestibility in early‐weaned pigs

Abstract

Zusammenfassung Der Einfluß des Rohproteingehaltes in der Ration auf die ileale undfekale Aminosäuren‐Verdaulichkeit bei frühabgesetzten Ferkeln Der Einfluß des Rohproteingehaltes in der Ration auf die ileale und fekale Verdaulichkeit des Rohproteins und der Aminosäuren wurde an 12 Ferkeln (Yorkshire × Landrasse), die nach drei Wochen abgesetzt wurden, untersucht. Die Ferkel waren mit einer einfachen T‐Kanüle am distalen Ileum versehen und erhielten vier Rationen auf der Basis von Maisstärke mit 16,5, 19,5, 22,5 und 25,5% Rohprotein aus Sojabohnenmehl. Die Ferkel wurden viermal täglich um 02.00, 08.00, 14.00 und 20.00 Uhr gefüttert und erhielten 5% (w/w) ihres durchschnittlichen Körpergewichtes, das jeweils am Beginn der Versuchsperiode ermittelt wurde. Jede Versuchsperiode umfaßte 9 Tage. Kot wurde an Tag 6 und 7 gesammelt, ileale Digestaproben wurden an Tag 8 und 9 genommen. Zur Bestimmung der Verdaulichkeit wurde Chromoxid als Marker zugesetzt. Es konnten keine Unterschiede (P > 0,05) in den scheinbaren ilealen Verdaulichkeiten beim Rohprotein und bei den Aminosäuren in Abhängigkeit vom Rohproteingehalt in der Ration beobachtet werden. Die durchschnittlichen ilealen Verdaulichkeiten für die essentiellen Aminosäuren lagen bei 84,2, 84,6, 83,3 und 83,2% mil 16,5, 19,5,22,5 und 25,5% Rohprotein. Auf der Basis einer polynomialen Regressionsanalyse fielen die ilealen Verdaulichkeiten der meisten Aminosäuren linear (P < 0,05) bei steigenden Rohproteingehalten ab. Die fekalen Verdaulichkeiten wurden durch die Behandlung nicht beeinflußt (P > 0,05).

Estimates of basal ileal endogenous losses of amino acids by regression analysis and determination of standardised ileal amino acid digestibilities from casein in newly weaned pigs

“…36 Several authors assumed that a decline in AA digestibilities at higher dietary CP levels may reflect a limited digestive capacity of pigs. 9,22,36 However, with respect to SID obtained in the range of 90-220 g kg −1 CP the decline in SID at 415 g kg −1 CP in the diet was most pronounced for AA with a high contribution in endogenous secretions such as Thr and Gly suggesting that the absorption capacity for exogenous AA was not a limiting factor. Differences in the SID of all AA except for Gly, obtained in the range from 90 to 220 g kg −1 CP by regression analysis, did not exceed 3 percentage units in comparison to those determined at a dietary CP content of 415 g kg −1 .…”

“…20,34 Thus, there is no indication for a limiting capacity for CP digestion or AA absorption in newly weaned pigs fed casein as sole source of CP as was originally suggested by Li et al 22 using soybean meal as the sole source of dietary CP. In the present study, IAAL B amounted to 9.3 g kg −1 DMI (P < 0.001) for CP and ranged from 0.1 g kg −1 DMI for Met (P = 0.021) and Trp (P = 0.220) up to 0.9 g kg −1…”

“…A total of 14 three-week-old barrows (12 + 2 for replacement) (German Landrace Piétrain), with an initial BW of 5.7 kg, were surgically fitted with simple T cannulas at the distal ileum according to the procedures adapted from Li et al 22 The pigs received in total six semi-synthetic corn starch-based diets with graded inclusion levels of casein, added to the experimental diets at the expense of corn starch, and resulting in CP contents of 90, 155, 220, 285, 350 or 415 g kg −1 (as-fed basis, Table 1). The experimental animals were completely randomised to the six dietary treatments.…”

Effect of micronization on energy, starch and amino acid digestibility in hulless barley for young pigs

“…Third, BW (age) may affect digestibility values, at least in young pigs. The digestibility values in studies with young pigs fed corn starch-based soybean meal diets have been reported to be lower (P < 0.05) during the first than during the second experimental period (Li et al 1993;, but similar (P > 0.05) in another study ). Fan and Sauer (1995), in studies with older pigs (BW: 40-70 kg) in which the difference method was used also, reported ileal lysine and threonine digestibilities of 61.3 and 62.4% in hulled barley, respectively, which compare to 56.1 and 55.6% respectively, with young pigs (BW: 7.1-15.9 kg) in the present studies.…”

Effect of common antinutritive factors and fibrous feedstuffs in pig diets on amino acid digestibilities with special emphasis on threonine1,2

“…On arrival, the pigs were fed a commercial starter diet (Consultant Feeds, Calmar, Alberta, Canada) for 3 d before surgery. After a 12-h fast, the pigs were surgically fitted with a simple T-cannula at the distal ileum, as described by Sauer (1976) and Li et al (1993). Cannulas were approximately 3 mm in wall thickness, with a 13-mm internal barrel diameter; wings were 16 mm in diameter and 40 mm in length.…”